On Nutrition: How things work

Barbara Intermill, Tribune News Service on Jul 10, 2026

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When I was in graduate school, I’m sure I annoyed my biochemistry professor. I didn’t mean to. It was just that, at that point in my education, I really needed to understand how the complicated formulas he wrote on the board related to human health. Perhaps that’s why his eyes rolled each time I raised my hand.

Although this particular educator did not seem to share my enthusiasm for understanding the how, his class launched me into a lifelong fascination with how various substances in food translate into human nutrition needs. Here are three examples of how things work:

Many people take psyllium fiber to prevent constipation. But how does this particular form of dietary fiber—made from the husk of the psyllium seed—work?

Psyllium’s ability to prevent constipation is due to its “insoluble” fibers that bulk up the stool and speed its travel through the digestive tract.

Yet most (80%) of psyllium fiber is the “soluble type,” which has additional benefits. When added to water, this type of fiber forms a sticky, soft gel. As it makes its way through the gut, this soluble fiber takes extra cholesterol and sugar along with it. This may explain why psyllium fiber is associated with lowering cholesterol and blood sugar levels … along with helping to prevent constipation. Just remember to drink plenty of water along with any fiber supplement.

How does cranberry juice help prevent urinary tract infections? Certain chemical components in cranberries have what researchers describe as “anti-adhesive activity.” Some studies have shown that these cranberry-derived substances protect the lining of the bladder so that E. coli—the bad bacteria responsible for 70-90% of urinary infections—cannot dig in to reap havoc. And 100% unsweetened cranberry juice works best, say experts.

Lastly, I’m not a huge fan of dietary supplements that haven’t been scrutinized as closely as prescription medicines. Still, I was curious about the claims that red yeast rice may help lower blood cholesterol levels.

Red yeast rice (RYR) is derived from a fungus formed when rice is fermented. It gained attention when scientists discovered that the main component in red yeast rice (monacolin K) is structurally identical to a statin drug used to treat high cholesterol.

In 2024, a systematic review of clinical studies on red yeast rice was published in the journal Nutrients. These authors reported that, indeed, RYR showed an ability to reduce total cholesterol and LDL cholesterol levels with no life-threatening side effects.

At the risk of being annoying however, Consumer Labs tested several brands of RYR supplements and found few that contained enough of the active ingredient to actually lower cholesterol. Prescription statin medications offer more consistent and safe doses.

Also, even though RYR may be safe to take, if it works like a statin, it may have the same side effects of statin drugs. Most notable are digestive upset and muscle pain.

And that’s how it works.